For no particular reason, I just worked out that if you start...

For no particular reason, I just worked out that if you start with a $50 note, and the stack grows at 20% PA, you would have a stack of notes growing at the speed of light after only 180 years, at which point the stack would be 60 trillion kilometers high.
(The calculation ignores elastic compression and assumes no voids as well as no influence on the speed of light by the gravitational attraction of the notes.)
Alternatively, with the same caveats, after 750 years you would have spherical ball of $50 notes expanding at the speed of light and it would be roughly 35 light years in diameter.

Now unless these investment geniuses can be persuaded to tell us how they are doing it, does anyone have anything useful to say about SDI?

I know, I know, I should keep taking the happy pills.